1. Field of the Invention
The invention relates to a stable succinyl peroxide composition and a method of preparation thereof.
2. Description of the Prior Art
Succinyl peroxide, which is also known as disuccinyl peroxide or succinic acid peroxide is a compound of the formula: EQU (HOOC.CH.sub.2.CH.sub.2.CO).sub.2 O.sub.2
Succinyl peroxide is known for use as a polymerization initiator, as a deodorant and as an antiseptic. In the past the compound has been sold in the dry powder form for use as a polymerization initiator, but it was found that the dry powder is friction sensitive and, under certain circumstances, could explode. In order to overcome this problem succinyl peroxide is currently marketed as a 70 percent by weight paste in water.
However, succinyl peroxide as a paste in water is unstable at ambient temperatures, the peroxide decomposing by hydrolysis, and stability can only be ensured by storing the paste under refrigerated conditions, typically at -10.degree. C. It will be appreciated that the need to store and transport the paste under refrigerated conditions is a significant disadvantage, especially when the succinyl peroxide is required for use in applications where for instance relatively small unit doses of the peroxide are to be stored before use, for example, as an antiseptic.
The encapsulation of perphthalic acids in protective coatings of hydrated or partially hydrated salts such as partially hydrated and hydrated magnesium and sodium sulfate is described in the prior art, e.g., see U.S. Pat. Nos. 3,494,786 and 3,494,787 to Nielsen, and U.S. Pat. No. 3,622,366 to Piester.
U.S. Pat. No. 3,639,285 to Nielsen discloses that the stability of monoperphthalic acids can be substantially improved by incorporating therewith certain alkali metal and alkali earth metal salts such as anhydrous magnesium and sodium sulfate.
British Pat. No. 1,456,591 to The Procter & Gamble Company describes bleaching compositions of excellent storage stability comprising a specified peroxyacid material, a peroxyacid-stabilizing agent mixture consisting essentially of a specified proportion of magnesium sulfate and a particular alkali metal sulfate, and a specified amount of bound water of hydration.
British Pat. No. 1,456,592 to The Procter & Gamble Company describes peroxy bleaching granules comprising, in specified amounts, a normally solid, organic, water-soluble peracid admixed with a bleach-stabilizing agent such as magnesium or sodium sulfate, water of hydration, and a fatty alcohol coating material.
Research Disclosure, September, 1974, No. 12510, pp. 4-6, teaches the stabilization of a peroxygen compound selected from p-nitroperbenzoic acid, diperazelaic acid and m-chloroperbenzoic acid by contacting spray droplets of the peroxygen compound with a fluidized bed of magnesium sulfate particles having a moisture content of less than 10%, and mixing for a time sufficient for the water content of the spray droplets to be bound by the magnesium sulfate to give a substantially dry and free-flowing magnesium sulfate coated peroxygen compound.
None of the foregoing references describe stable succinyl peroxide compositions.